目的研究不同前交叉韧带力学特性对膝关节有限元模拟结果产生的影响。方法基于医学图像数据重建包含主要解剖结构在内的膝关节三维有限元模型,并考虑韧带的横观各向同性特性;用同一种韧带本构方程对3种不同前交叉韧带应力应变力学实验曲线进行参数拟合,对比不同的前交叉韧带力学参数对膝关节运动学和生物力学性能的影响。结果不同的前交叉韧带力学特性会得到不同的膝关节位移结果,前交叉韧带内的应力及应变大小有很大变化,但分布的趋势基本相同。结论选取不同前交叉韧带力学特性曲线会影响膝关节有限元分析的仿真结果,今后在关节组织力学性能的设置、模型的构建及验证中要足够重视。
Objective To investigate the effect of mechanical properties of anterior cruciate ligament(ACL) on finite element simulation of knee joint.Methods A three-dimensional finite element model of knee joint including all the main tissues was reconstructed based on medical images,and the transverse isotropic hyperelasticity of ligament was considered as well.Three groups of ACL material property parameters were acquired by fitting three different experimental stress strain curves based on the same ligament constitutive equation,to compare the influence of different ACL mechanical parameters on the kinematic and biomechanical properties of knee joint.Results Different ACL mechanical properties resulted in different displacements in knee joint.With the change of ACL mechanical properties,the stress and principal strain in ACL changed a lot,while the trend of their distributions were basically the same.Conclusions The selection of different ACL experimental stress-strain curves can influence the simulating result of the finite element analysis.More attention should be paid to the determination of ACL mechanical properties,the reconstruction and validation for the finite element model of knee joint.